This research will be done primarily in Aleppo, Syria at the Syrian Society Against Cancer (SCTS) in collaboration with Wasim Maziek, MD, PhD, as an extension of NIH grant* R01TW005962. Drug dependence involves repeated self-administration of a psychoactive substance, despite known health risks, high financial costs, and multiple quit attempts. Tobacco dependence is a particularly lethal example, currently causing 4.9 million deaths worldwide each year, with this number expected to double in the next 20 years (World Health Organization [WHO], 1998). Of these deaths, 70% are expected to occur in developing countries (WHO, 1998). Despite the fact that developing countries bear the brunt of the epidemic, most tobacco research and treatment efforts do not consider tobacco use methods that are common in developing countries. Waterpipe use is common in many developing countries, including those in the Eastern Mediterranean region (EMR), and involves inhaling tobacco smoke that has passed through water. Millions use waterpipes daily, and growing evidence indicates that waterpipe use is a dependence-producing phenomenon. Understanding the extent and features of waterpipe dependence may be critical to reducing its negative health effects. Like cigarette smoking, waterpipe use is associated with cancer, cardiovascular disease, and impaired pulmonary function. Unlike cigarette smoking however, there are no interventions to help waterpipe users quit, perhaps because so little is known about the extent and features of dependence in waterpipe smokers. This proposal uses the SCTS' research strengths to further our understanding of waterpipe dependence and develop a waterpipe dependence measure. We propose to 1) further our formative work on waterpipe dependence features by conducting key informant interviews and focus groups with current and former waterpipe users; 2) develop a model and measure of waterpipe dependence, based on current theory in drug dependence and results of formative work; and 3) Test the measure in a sample of 600 waterpipe users to determine its psychometric properties, including predictive validity. Relevance to public health: Given the increasing worldwide prevalence of this deadly and potentially addictive form of tobacco use, understanding dependence potential and treating waterpipe users is a global health priority. [unreadable] [unreadable] [unreadable]